Implantable medical devices (IMDs) described herein, and methods for use therewith described herein, reduce how often an IMD accepts a false message and/or reduce adverse effects of an IMD accepting a false message. Such IMDs can be leadless pacemakers (LPs), or implantable cardio defibrillators (ICDs), but are not limited thereto. Such embodiments can be used help multiple IMDs (e.g., multiple LPs) implanted within a same patient maintain synchronous operation, such as synchronous multi-chamber pacing.

Computer implemented methods and systems are provided that comprise, under control of one or more processors of a medical device, where the one or more processors are configured with specific executable instructions. The methods and systems obtain motion data indicative of at least one of a posture or a respiration cycle; obtain cardiac activity (CA) signals for a series of beats; identify whether a characteristic of interest (COI) from at least a first segment of the CA signals exceeds a COI limit; analyze the motion data to determine whether at least one of the posture or respiration cycle at least in part caused the COI to exceed the COI limit. Based on the analyzing operation, the methods and systems automatically adjust a CA sensing parameter utilized by the medical device to detect R-waves in subsequent CA signals; and detect an arrhythmia based on a presence or absence of one or more of the R-waves in at least a second segment of the CA signals.

Methods, systems and devices for providing cardiac resynchronization therapy (CRT) to a patient using a leadless cardiac pacemaker (LCP) and an extracardiac device (ED). The LCP is configured to deliver pacing therapy at a pacing interval. Illustratively, the ED may be configured to analyze the cardiac cycle including a portion preceding the pacing therapy delivery for one or several cardiac cycles, and determine whether an interval from the P-wave to the pace therapy in the cardiac cycle(s) is in a desired range. In an example, if the P-wave to pace interval is outside the desired range, the ED communicates to the LCP to adjust the pacing interval.

A medical device is configured to deliver anti-tachycardia pacing (ATP) in the presence of T-wave alternans. The device is configured to detect a ventricular tachyarrhythmia from a cardiac electrical signal received by the medical device. In response to the detected ventricular tachyarrhythmia, the device delivers a plurality of ATP pulses at alternating time intervals. The alternating time intervals comprise at least a first ATP time interval separating a first pair of the ATP pulses and a second ATP time interval different than the first ATP time interval. The second ATP time interval consecutively follows the first ATP time interval and separates a second pair of the ATP pulses.

An extra-cardiovascular implantable cardioverter defibrillator (ICD) having a high voltage therapy module is configured to control a high voltage charging circuit to charge a capacitor to a pacing voltage amplitude to deliver charge balanced pacing pulses. The capacitor is chargeable to a shock voltage amplitude that is greater than the pacing voltage amplitude. The ICD is configured to enable switching circuitry of the high voltage therapy module to discharge the capacitor to deliver a first pulse having a first polarity and a leading voltage amplitude corresponding to the pacing voltage amplitude for pacing the patient's heart via a pacing electrode vector selected from extra-cardiovascular electrodes. The high voltage therapy module delivers a second pulse after the first pulse. The second pulse has a second polarity opposite the first polarity and balances the electrical charge delivered during the first pulse.

Systems, devices, and methods for monitoring for atrial capture are disclosed. Such a method, for use within an implantable system including an atrial leadless pacemaker (aLP) and a ventricular leadless pacemaker (vLP), includes storing within a memory of the vLP a paced atrial activation morphology template corresponding to far-field atrial signal components expected to be present in a vEGM sensed by the vLP when an atrial pacing pulse delivered by the aLP captures atrial tissue. The vLP senses a vEGM and compares a morphology of a portion of the sensed vEGM to the paced atrial activation morphology template to determine whether a match therebetween is detected. Additionally, the vLP determines whether atrial capture occurred or failed to occur (responsive to an atrial pacing pulse), based on whether the vLP detects a match between the morphology of a portion of the sensed vEGM and the paced atrial activation morphology template.

A system and methods of maintaining communication with a medical device for exchange of information, instructions, and programs, in a highly reliable manner. Apparatus and methods for accomplishing this task include: 1) The inclusion of a locating device in the system, in close proximity to an implanted device, but which does not drain the implanted device battery. 2) The use of motion detection and global positioning system devices to locate elements within a communicating system for the medical device; 3) The assessment of received signal quality by elements of the system; 4) The use of a notification system for a device user who is moving out of range of communications; and 5) Documenting the absolute and functional integrity of instructions received by the medical device. A method of assuring the identification of communication participants is presented.

A medical device is configured to receive cardiac electrical signals and sense ventricular event signals from the cardiac electrical signals. The medical device may start a validation window in response to sensing a ventricular event signal and determine if the ventricular event signal is a valid event signal or an invalid event signal based on processing of a different cardiac electrical signal than the cardiac electrical signal from which the ventricular event signal was sensed.

A medical device is configured to sense an electrical signal and determine that signal to noise criteria are met based on electrical signal segments stored in response to sensed electrophysiological events. The medical device is configured to determine an increased gain signal segment from one of the stored electrical signal segments in response to determining that the signal to noise criteria are met. The medical device determines a noise metric from the increased gain signal segment. The stored electrical signal segment associated with the increased gain signal segment may be classified as a noise segment in response to the noise metric meeting noise detection criteria.

A pacing device, a system comprising the pacing device and a method for operation of the pacing device, wherein the pacing device comprises a housing, a processor and a receiver electrically connected to the processor, wherein the processor is adapted to deliver signals for electric stimulation of a patient's heart according to at least one first stimulation mode and deliver signals for electric stimulation of the patient's heart according to an antitachycardiac pacing mode (ATP mode), wherein the ATP mode is initially deactivated and/or is to be upgraded, wherein the receiver is adapted to receive an ATP confirmation signal transmitted by an external device or produced by operation of an actuator accommodated at the housing of the pacing device, wherein the processor is adapted to upgrade the ATP mode and/or to activate the ATP mode only if the ATP confirmation signal comprises a pre-defined confirmation information.